• Advances in concrete construction
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• v.10 no.5
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• pp.455-462
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• 2020

This study investigated the effect of horizontal casting joints on the mechanical properties and structural behavior of sustainable self-compacting reinforced concrete beams (SCRCB). The experimental research consisted of two stages. The first stage used four types of concrete mixtures which were produced to indicate the effects of cement replaced with cement waste at 0%, 5%, 10%, and 15% by weight of cement content on fresh concrete properties of self-compacting concrete (SCC) such as, passing ability, filling ability, and segregation resistance. In addition, mechanical properties such as compressive, tensile, and flexural strength were also studied. The second stage selected the best mixture from the first stage and studied the effect of horizontal casting joints on the structural behavior of sustainable SCRCBs. The effect of horizontal casting joints on the mechanical properties and structural behavior were at the 25%, 50%, 75%, and 100% of sample height. Load deflection, failure mode, and theoretical analysis were studied. Results indicated that the incorporation of replacement with cement waste by 5% to 10% led to economic and environmental advantages, and the results were acceptable for fresh and mechanical properties. The results indicated that delaying the time for casting the second layer and increasing the cement waste in concrete mixtures had a great effect on the mechanical properties of SCC. The ultimate load capacity of horizontal casting joints reinforced concrete beams slightly decreased compared with the control beam. The maximum deflection of casting joint beams with 75% of samples height is similar with the control beam. The experimental results of reinforced concrete beams were substantially acceptable with the theoretical results. The failure modes obtained the best forced casting joint on the structural behavior at 50% height of casting in the beam.

• Korean Journal of Organic Agriculture
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• v.12 no.1
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• pp.93-99
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• 2004

This study were conducted to determine the optimum warm casting rate(0, 100, 200, 300, 400, 500kg/10a) for the yield of food canna in jeju island. The plant height was ranged from 109.4 to 1347cm as organic fertilizer of worm casting increased from 0 to 500kg/10a, but it was no significance between 400 to 500kg/10a. Leaf length, leaf width, number of leaves, number of tillers and bulb per plant were shown higher as the amount of worm casting was increased. Stem diameter were the same trend with plant height response. Fresh yield of food canna increased significantly 134 to 22.6MT/ha as fertilizer rate increased from 0 to 500kg/10a. Fresh weight of above-ground pan and blub were shown the same trend with fresh yield of food canna.

• Journal of Korea Foundry Society
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• v.35 no.3
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• pp.62-66
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• 2015

Tape casting is an important forming operation used to prepare flat sheets in the various industries. In this study, Doctor Blade tape casting of In-based low melting point alloy was carried out. The purpose of this investigation was to determine the possibility of applying the Doctor Blade tape casting process to the manufacture of low melting point alloy sheets that can be used as thermal fusible parts of battery safety systems. In-based molten alloy that has a melting point of $95^{\circ}C$ was produced; it's viscosity was measured at various temperatures. The molten alloy was used as a slip in the caster of the Doctor Blade tape casting system. The effects of the molten alloy temperatures and carrier speeds on the produced sheet shape were observed. For the casting conditions of 1.5 cm slip height, $120^{\circ}C$ slip temperature, 0.05 mm blade gap and 60 m/min. carrier speed, an In-based alloy thin tape well shaped with 0.16 mm uniform thickness was continuously produced.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.130-138
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• 2015

In this study, to examine the application of cast-in-place of high-flowable and high-strength concrete, an experimental study on the lateral pressure of a formwork was preformed. The experiment specimens, which have different casting height and casting speed were prepared. The lateral pressure and the change of temperature from test specimens were obtained. The maximum lateral pressure was shown to lateral pressure of fresh concrete. Immediately after placing, the lateral pressure starts to decrease and, after 12 hours, it showed a stabilization. The decreased tend of the lateral pressure was similar with normal-strength concrete, which appears stabilization after 3~4 hours from casting completion. The more casting speed is fast, the more maximum lateral pressure is high, but pressure reduction with the lapse of time was nearly similar. In addition, it was found that there was no direct relation between the hydration heat and the lateral pressure reduction.

• Journal of Korea Foundry Society
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• v.37 no.6
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• pp.173-180
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• 2017

In this paper, the casting design of the integrated twin-scroll turbine housing with exhaust manifold using stainless steel is investigated. Due to the complexity in its geometry and the poor castability of stainless steel, it is more crucial to set up the appropriate casting design to avoid casting defects. Gas porosity and shrinkage formation with the changes of gating systems (one-/two-side), riser conditions and pouring temperatures are examined via casting simulation and virtual castings. Simulation results show that two-side gating system produced better quality casting than that of one-side gating system, minimizing the gas content of the castings and it is also verified by X-ray analysis for the virtual castings. For the changes of riser conditions and pouring temperatures in the two-side gating system, it is found that the change of the height of two risers plays an important role in obtaining the best quality by reducing shrinkage defects.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1364-1367
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• 1996

Recently, direct rolling process, called as strip casting process, has been interested in to save production cost by reducing forming processes. In direct rolling process, since a steel strip of thickness 1-5(mm) can be produced directly from molten metal, it can eliminate secondary hot rolling process. On the other hand, since many process variables are existed in this process and relation of these variables is very complex, it is difficult to realize the process design and the quality control. In this paper, as first step to overcome above difficulties, the quantitative relationship of the process variables affected to quality of the strip has been carried out through the numerical analysis. Also, we determined the process variable to monitor the quality in the direct rolling process. As a result, we show that the solidification final point, called as Nip point, was related directly to quality of the strip.

• Plant Resources
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• v.7 no.3
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• pp.170-173
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• 2004

To determine optimal plant density of forage rye in southern areas of Korea, forage rye cv. Paldanghomil, the highest yielding variety among experimental varieties of forage rye, was grown under five different plant density. Yield components such as plant height, and number of leaves were highest at the broad casting. Plants sown at broadcasting also showed highest fresh and dry matter yield. When plants were grown of the broad casting, they showed higher values in content of crude protein and lower values in contents of crude fiber such as neutral detergent fiber(NDF), acid detergent fiber(ADF), cellulose and lignin. There was no relationship between variation of in vitro dry matter digestibility(IVDMD) and plant density. Plants sown at the broad casting showed highest digestible dry matter yields.

• Journal of the Korean Ceramic Society
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• v.28 no.8
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• pp.577-584
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• 1991

Among various forming techniques for ceramics, we have studied the slip casting method for the binary system of SiC and carbon. The stability of the slip of silicon carbide and carbon were investigated by measurements of zeta potential, viscosity, sedimentation height, and also studied as functions of PH and amounts of dispersants. A preform of SiC and C was prepared by slip casting and heat treatment at 400∼600$^{\circ}C$ under N2 gas. The preform was reacted with Si metal at 1550$^{\circ}C$, 10-1 mmHg to give rise a reaction bonded SiC with a density of 3.0g/㎤ and a bending strength of 580 MPa.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.1
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• pp.27-35
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• 2006

The aim of this study was to identify the sources of benzene detected in airborne of casting workplace where benzene was not used as raw material. We have identified benzene by GC/FID and GC/MSD. In this pilot test, small size iron chamber(diameter 30 cm, height 20 cm) was used. As the raw materials, new sand, recovered sand, and mixed casting sand(new sand + solidifying agent + organic resin + coating material) was tested, respectively. In the new sand benzene was not detected, but in the recovered sand and the mixed casting sand was detected. Xylenesulfonic acid(solidifying agent), one of the mixed casting sand ingredients was thought to product benzene by thermal decomposition above $400^{\circ}$..., but the other raw materials(organic resin and coating material) were thought not to product benzene. In this experiment, the most of benzene by thermal decomposition was produced within 1 hour after pouring the iron solution($1560^{\circ}$...) in small size iron chamber. When the mixed casting sand with coating material was used, the concentration of the produced benzene was average 2.91 ppm(range 1.98~3.72 ppm), and without coating material, benzene concentration was average 0.11 ppm(range 0.08~0.14 ppm).

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.196-200
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• 1987

In this paper A NET-CUE System is designed and implemented for tramsmission of the network cuing informations with using data packet broad casting techniques. This system is composed with encoder and decoder. To show the performance of this system An eye height and bit error rate are cheched. The eye height is greater than 74% and The bit error rate is less than 4.6 * 10 The exper imental results show that this system provides a good quality of the operation.